Rotary connecter



i-June 11, 1929. R. F. STEHLIK 1,716,986

ROTARY CONNECTER Original Filed June 29, 1925 77 :IZ-lalzllzcxmmm Patented June 11, 1929.

UNITED STATES PATENT OFFICE.

RUDOLPH F. STEHLIK, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO AUTOMATIC ELECTRIC INC., F CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE.

ROTARY CONNECTER.

Application filed .Tune 29, 1925, Serial No. 40,239. Renewed October 29, 1928.

The present invention relates to improvement-s in switches of the type known as rotary connectors, and may be considered as an improvement on the connecter shown in the application ot' John E. Ostline, Serial No.

758,998, filed December 3l, 1924.. Such switches are provided tor the purpose of establishing connections to an idle line of a group oi. lines which are allotted the same lo number in the directory. The switches used are of the` two directional type having ten levels ot ten sets ot contacts in the level.

"he contacts in a level may be arranged in one or a plurality of groups, dependingl l5 upon the size ot' the groups in question. For

night service it is otten desirable to plug one or( several lilies through the attendant-s switchboard to individual telephones and for this purpose a special number is allotted in ao the director)T for each telephone, which is different trom the number allotted tor day service. The number allotted for day service corresponds to that of the first line ot the group, while those allotted for night service correspond to successive lines in the group. It is desirable that when the number ot the first line is called, it the first line is busy, the switch should automatically rotate and como to rest on the first idle line ot a group and turther that it should stop when the last line is reached and give the busy signal if all the lines in a group are busy, while if a night number is called, and the latter number is busy, the busy signal is given immediately and no hunting takes place over the remaining lines of the group.

It is the object ot the present invention to evolve a rotary connecter for bringing about the above results, which is ot the same construction as that used when night service YFacilities are not provided, the only alterations effected being those concerning the circuit arrangements of the switch. According to the present invention this is etliected by arranging an automat-ic rotary control circuit, which is isolated from 'the private test circuit., and connecting up the contacts wiped over by the rotary control wiper ot the switch in three different manners depending upon their position in the group.

In order that the invention may be clearly understood and readily carried into effect, a connecter switch in accordance with the invention will now be more fully described,

reference being made to the annexed drawing, which is a diagram of connections ot the invention.

The switch, being of the two direction type, has the usual vertical and rotary magnets for controlling its selective operation. and also has a release magnet for releasing the switch to normal position. The switch has associated with it the usual ringing current and busy tone sources. The switch shat't carries the usual line Wipers and in this case two test wipers-a private and a special wiper. The wipers wipe over the bank contacts ot the desired group, the first special. wiper contact of which is connected. to battery, the last of which is grounded, while the intermediate contacts are left unconnected. Y

The apparatus having been described more or less in general, a detailed description ot the operation of the connecter shown in the drawing will now be given. For this purpose, it will be assumed that an automatic subscriber desires to obtain connection with a subscriber in a private branch exchange served by a group of trunk lines. The customary subscriber-s substation, individual line switch, and selector switches as used by an automatic subscriber in completing a con-- nection are not shown but are well understood "by those skilled in the art and torm no part of the present invention. It will therefore suflice to say that in response to the removal of the receiver by the calling subscriber, his individual line switch seizes an idle trunk line leading to an idle selector switch. and in response to the operations ot the subscribers calling device, the selector switches are operated to select an idle trunk line leading to a connecter switch.

Let us assume that the calling subscriber has established his connection as far as the last selector. and that the selector has come to rest on bank contacts connected to the conductors 20, 21, and 22 ot the connecter switch shown in the drawing, this being the first idle connecter accessible to the said selector. VVhen the selector switch comes to rest upon the contacts associated with conductors 20, 21, and 22, the switching relay ot the selector completes an energizing circuit for the line relay 4 of the connecter switch as follows: from ground by way of the lower winding of line relay 4, normally closed springs controlled by armature 31 of relay 3, conductor 21, over the intervening switches and the subscribers loop back to conductor 20, normally closed springs controlled by armature 30, and througli the upper winding of line relay 4 to battery. Relay 4 at armature 33 and its working contact completes an energizing circuit for the slow to release relay 5.' Relay 5, upon energizing, connects ground to the release trunk conductor 22 at armature 34 and its working Contact. This ground completes a holding circuit for the switches preceding the connecter switch for maintaining said switches in an operated position, and in addition, maintains the trunk line leading to the connecter busy to all other selectors having access thereto. Furthermore, relay 5, at armature 3G and its working Contact, prepares a. circuit for the vertical magnet 15 and at its rest-ing Contact opens a point in the release circuit; and at armature 35 and. its working contact grounds the holding conductor G5.

The calling subscriber may now manipu-v late his calling device in accordance with the remaining digits in the number of the private branch exchange, which in this case are assumed to be 1 and 1. In response to the next operation of the calling device by the calling subscriber, the circuit of the line relay 4 is interrupted in known manner and the relay therefore dcenergizes for a short interval. A circuit `may now be traced for the vertical magnet 15 as follows: from ground by way of armaturc'33 and its resting Contact, armature 36 and its working contact, normally closed contact and off-normal spring G2, slow to release series relay (i. and vertical magnet 15 to battery. The vertical magnet 15 and relay G energize in series and by the operation of the vertical magnet 15, the shaft and wipers are raised until the wipers to 73, inclusive, are opposite the first level. Relay 6 maintains its own circuit and that of the vertical magnet. intactafter the shiftingof the olf-normal springs which takes place on the first vertical step. After the first impulse, since there is only one in this case, the line relay 4 energizcs again and opens the circuit for relay 6 and vertical magnet 15 at armature 33. Relay 6, upon deenergizing after a short interval, transfers the impulsing circuit from the vertical magnet to the rotary magnet at armature 37.

Upon the dialling of the final digit of the called subscribers number, in this case the digit 1, the circuit of lrelay 4 is again interrupted. The line relay 4, upon deencrgizin'g,conipletes parallel circuits for the rotary magnet 1G and relay Y11 as follows: from ground, armature 33 and its resting contact, armature 36 and its working contact, 'normally open contacts controlled by off-normal spring G2, armature 37 and its resting contact, resting contact and arman ture 49, and through relay 11 to battery, and also continuing by way of armature 57 and its resting contact, resting contact and armature 42, through rotary magnet 1G to battery. The rotary magnet 16 and relay 11 energize in parallel. The rotary magnet 1G steps the wipers 70-73, inclusive, into engagement with the bank contacts 74-77, inclusive, of the first trunk in the first level. Relay 11, upon energizing, at armature 53 and its working contact shunts armature 49; at armature 52 and its resting contact opens the circuit of the switching relay 12; at the working contact of the same armature prepares a circuit for test relay 10; and at armature 54 prepares a circuit for relay 9. It may be stated now that since the First set of bank contacts in the first level are those of the first line of the group, the bank contact 7 5 will have battery connected thereto. Furthermore let it be assumed that the first line of the group is busy, that is, the bank contact 74 is grounded by the test wiper of another connecter. The ground on bank contact 74 energizes test relay 10 by way of wiper 70, normally closed contacts controlled by armature 44, armature 43 and its resting contact, armature 52 and its working Contact, resting contact and armature 58, normally closed contacts controlled by armature 45, normally closed contracts controlled by armature 43, resting contact and armature G0, and test relay 10 to battery. Relay 10, upon energizing, at armature 49 opens a point in the rotary impulsing circuit, at armature 48 prepares a lock-circuit for itself, at armature 51 connects the busy machine, and atar-mature 50 closes a circuit for4 relay 9 which may be traced from grounded holding conductor 65, upper winding of relay 9, armature 50 and its working contact, working contact and armature 54, wiper 71, and bank cor.- tact 7 5 to battery. Relay 9, upon energizing, at armature 47 prepares a locking eircuit for itself; at armature 44 closes a new holding circuit for relay 10 before the original operating circuitl opens; at armature 6G opens the circuit of the busy signal; and at armature 45 prepares an energizing circuit for stepping relay S. A short interval after the rotary impulse is terminated the slow to release relay 1x1 deenergizes and a `r normally closed contacts controlled by armature 54 a locking circuit .is closed for relay 9 which may be traced from groifinded holding conductor G5, upper winding of relay 9, armature 50 and its working Vcontact, normally closed contacts controlled by armature 54,'working contact and armature 47, and lower Winding ofrelay 9 to battery. This locking circuit is closed before the original operating circuit opens due to the make before break contacts controlled by the circuit closing armature. It will be observed from this locking circuit that the windings of relay 9 oppose each other, however, the ampere turns of the upper winding being tar in excess of the lower winding, the upper winding continues to receive sufficient current to hold the relay in operated position. As a further result ot the deenergizalion ot' relay 11, armature 52 closes a circuit for relay S, which may be traced trom grounded release trunk conductor 22, armature 48 and its working contact, normally closed contacts controlled by armature 52, resting contact and armature S, working contact and armature 45, resting contact and armature G4, and relay 8 to battery. Relay 8, upon energizing, complelesA at armature 41 a locking circuit for itsell; and at armature 42 closes a circuit for rotary magnet 1G, which may be traced trom ground on the release trunk conductor Q2, working contact and armature 42, and rotary magnet 1G to battery. Rotary magnet 1G, upon energizing, advances the wipers 70-73, inclusive, into engagement with the next. set of bank contacts which, as will be seen 'from the drawing, has its contact 78 'free 'trom battery or ground potential. Rotary magnet 16, at its interrupter contact 64, opens the circuit ot stepping relay S and the latter falls back and opens the circuit ot the rotary magnet at armature 42, as well. as opening its own locking circuit at armature 41. It the test contact ot the next trunk is .tree relay will be deenergized to prevent stepping relay S from energii/.ing and stepping the switch turther as will be explained hereinafter in connection with the last trunk in the group being idle. Il" the second trunk is busy its test contact will be grounded and relay 10 will be held energized. Relay 8 will again become energized over a circuit previously traced. whereupon the rotary magnet 16 will again energize to rotate the wipers .into contact with third trunk. This alternate operation ot relay 8 and rotary magnet 1G continues until an idle trunk is found or until the last trunk in the group is reached.

The last trunk ot each group has its lower contact such as 79 grounded, and if the last trunk is busy the contact engaged by wiper 70 will also be grounded. lVhen wiper 71 vcomes to rest upon contact 79, which is grounded, relay 9 will no longer hold energized due to this ground being connected at a` junction point in the previously traced locking circuit ot relay 9, between its two windings. thus shunting out the upper w1nding and establishing a direct circuit for the the polarity of the relay coil and causes the relay to quickly deenergize and unlock. Relay 9, upon deenergizing at armature 4G opens its locking circuit; at armature prevents the stepping relay 8 from re-eners gizing; and at armature 44 opens the locking circuit of relay 10 by way ot wiper 70. However. on account of relay S being deenergized at this time a locking circuit tor relay 10 is closed by normally closed makebefore-break contacts controlled by arn'iature 45, which may be traced from grounded release trunk conductor 22, arn'iature 48 and its working contact, normally closed contacts controlled by armature 52, resting contact and arn'lature 58, normally closed con tacts controlled by armature 45, normally cl d contacts controlled by armature 113, re, ting contact and armature Gt), and relay 1() to battery. Should relay 9 deenergize before relay S deenergizes a locking circuit is still maintainedl'or busy relay l() due to the malte-betore-break contacts controlled bv armature 43 ot relay 8. As a further result of the deenergization ot relay 9, the circuit including the busy machine is closed at armatin'e 6G, thus giving the calling party the usual busy signal. n l

The calling party upon hearing the busy signal will replace his receiver upon the switchhook whereupon line relay 4 will deenergize and open the circuit of slow to release relay 5 at armature 33. Slow to release relay 5 upon deenergizing disconnects groun l itroin the holding conductor G5 at armature 35 and also disconnects ground from the rclease trunk conductor 22 at armature 34, whereupon relay 1() deenergizes and the preceding switches are released in known manner. As a further result of the deenergizatien ot relay 5, armature 36 completes the tollowing circuit for release magnet 14; trom grrround, armature 33 and its resting contact` armature 36 and its resting contact, ott-nor-v mal spring 13 and its working Contact, and release magnet 14 to battery. By the operation of the release magnet the switch shaft and wipers to 73, inclusive, are restored to normal whereupon the off-normal springs 13 and G2 are shifted, thus opening the eircuit ot the release magnet 14 which thereupon deenergizes. i

Returning now to the operation ot the connecter when it established connection with the last line of a group, We will assume that this line was idle and give a detailed description ot the operation ot' the connecter under these circumstances. It the last line ot the group is idle no ground potential will be encountered by test wiper 70 and busy relay 10 will deenergize, thus disconnecting the busy tone machine. Relay 9 will deenergize due to ground being encountered on the last lower contact as already explained. Battery potential through the cutoff relay and rotary magnet of the wanted subscribers line switch (not shown) will now be encountered by tcst wiper 70, and the following circuit will be completed for switching relay 12, battery through the rotary magnet and cutotl:1 relay ot the line switch ot the wanted line to test wiper 70, t-bc normally closed resting contact controlled by armature d4, armature 43 and its resting contact, armature 52 and its resting contact, upper winding ot relay l2, resting contact and armature 48, to `ground on the release trunk conductor ,Switching relay l2 and the line switch cut-oil relay energize in series over the above traced circuit. The cut-oft relay energizes slightly before the switching relay l2 owing to the core ot the latter rel ay being provided with a copper collar at its armature end. This is done to insure that the cut-ott relay will have disconnected the normal battery and ground connections from the called line before the switching relay connects ringing current thereto. Switching relay 12, upon energizing, con'iplctes at armature 59 a locking circuit it'or itselt to ground at the holding conductor 65, at armature GO opens a point in the circuit et busy relay l0; at arnniture 5G grounds the test wiper at armatures 55 and 6l. connects interrupted ringing current from the, ringing machine GEN. to the line wiper The calling subscriber is given the well known ringing tone, when riging current is applied to the wanted line, through the small acapacity condenser 80, which is connected across armature 38 and its working con` tact.

The wanted subscriber upon removin g his receiver in response to the ringing ot his bell, completos the following `circuit tor the ring cut-oli41 relay 7; grounded generator or grounded Contact at armature 63, resting contact and armature 40, armature 6l and its working contact, wiper 73, over the wanted partys loop to wiper 72, working contact and armature 55, armature 38 and its resting contact and the upper winding of relay 7 to battery. The ring cut-oil relay 7 cnergizes over the above traced circuit and completes a locking circuit for itself at arma` ture 39, and at armatures 38 and l() breaks the ringing current and completes the talking circuit between the calling and called subscribers. In addition, relay 7 completes a circuit for the back bridge relay 3 as lollows, 'l'rom ground, lower winding ot said relay by way of working contact and armature 40, armature Gl and its working contact, wiper T3 over the called partys loop to wiper 72, working Contact and armature 55, armature 38 and its working contact, to upper winding of said relay and battery. The backbridge relay, upon energizing, reverses the low of current to the calling subscriber at armatures 30 and 3l. After the conversation has been completed the release ot the connection takes place in the hereinbetore described manner upon the calling party replacing his receiver upon the switchhook, with the difference that relay l0 is 'now already deencrgized while the switching relay Yl2 and ringing relay 7 are deenergizcd when ground is removed from the holding conductor 65.

A brief description will now be given ot the operation which takes place when a number corresponding to an intermediate trunk of a group is dialled. Referring to the initial energizing circuit of stepping relay 8, it will be seen that this relay can only be energized through being connected to ground on the release trunk by way oit relays 9 and l0 being energized and relay ll being deei'iergized. Further, since'relay 9 cannot energize except with the test wipers standing on the first trunk and as a rcsult ot the energization of relay l0, it will be assumed that the irst trunk is found busy when the wipers reach the contacts of that trunk. Relays l0 and 9 will energize as already explained, but relay 9 cannot now lock up due to relay ll remaining energized during rotation, and will. dcenergize along with relay l0 as soon as the test wipers step off oi" the tirst trunk contacts. Relay l0 may, or may not, reenergize upon reaching the next trunk contacts depending upon whether the trunk is busy or not, but is ot no consequence at this time. Relay 9, however, cannot reenergize after passing the first trunk until after the switch is released and set over again. Relay 8, therefore,cannot energize under these circumstances and since this relay controls the circuit for rotary magnet t6, no hunting will take place. This Ylfeature is ot great practical use as it enables any line oit a group except the lirst to be listed in the directory lor night service.

Having described the invention, what is considered to be new and desired to have Yprotected by Letters Patent will be pointed ont in the appended claims.

that is claimed is:

l. ln a telephone system, a rotary connecter switch, a group oll lines accessible to said switch, each line having'a regular and a special test Contact, a cut-ott relay connected to each regular test contact, and dit'- Ylierent poles ot a battery permanently connected respectively to the lirst and last ofv 3. In a telephone system, a rotary connecter switch, a group of lines accessible 'to said switch, each line having a regular and a special test contact, a cut-off relay connected to each regular test contact, a resistance, and a battery having one pole connected to the first of said special test contacts through said resistance and the other pole connected direct to the last of said special test contact-s.

Ll. In a telephone system, a rotary connecter switch, a group of lines accessible to said switch, each line having a regular and a special test contact, a cut-ofi' relay connected to each iegular test contact, and a battery having one pole normally connected to the first of said special test contacts and the other pole normally connected to the last of said special test contacts, means for directively operating said switch to select any line of said group, and mea-ns in said switch controlled from the test contacts of the selected line and effective to cause the switch to hunt an idle line only in case the selected line is the first line of the group.

5. In a telephone system, a rotary connecter switch, a group of lines accessible to said switch, each line having a regular and a special tcst contact, said contacts being unconnected with each other, a cut-off relay connected to each regular test contact, and a battery having one pole connected to the first of said special test contacts and the other pole connected to the last of said special contacts, means for directively operating said switch to select any line of said group, and means in said switch controlled from the test contacts of t-lie selected linefor preventing any limiting action of the switch unless the selected line is the first line of the group.

6. In a telephone system, a switch having two test wipers, a group of lines, eacliline having test contacts accessible to said wipers,

CFI

means for operating said switch to select the first line of said group, automatic means controlled over' both said wipers for starting said switch rotating in search of an idle line if the first line is found busy, automatic means controlled over one of said test wipei's alone for continuing the hunting movement if the intermediate lines are found busy, and automatic means controlled over the other said test wiper for stopping the hunting movement when the last line is reached whether the last line is busy or idle.

7. Ina telephone system, a switch having two test wipers and a group of regular and special test bank contacts, automatic means controlled over both said wipers for starting said switch rotating in Search of an idle regular contact when the first regular contact is found busy, automatic means controlled over one of said test wipers for continuing the hunting movement when the intermediate two test wipers and two sets of bank contacts, a. test relay, a rotary series relay, meansincluding the energization of said series relay for connecting said test relay to the first of one set of said contacts over one wiper, means responsive to said connection for energizing said test relay when said contact is busy, a third relay, means including the energization of said test and series relays for Yconnecting said third relay to the first of the other set of said contacts over the other wiper, and means responsive to the energization of said third relay and the deenergization of said series relay for opeiating said switch in an automatic limiting movement. f

9. In a telephone system, a switch, groups of lines terminating in said switch, each group including more than two lines, means for directively operating said switch to select any line in any group, means effective only in case the first line in a group is selected for causing the switch to hunt for an idle line, a set of test contacts for each line comprising` a regular and a special test contact, and suitable circuit connections to the first and the last of said special test contacts for permanently connecting different poles of battery thereto for controlling the hunting operation of the switch.

l0. In a telephone system, a switch, a test contact accessible to said switch and having one pole of a battery permanently connected thereto, a second test contact accessible to said switch and having the other pole of said battery connected thereto, means for operating said switch to select said first contact, means operated responsive such selection by current from said battery for causing said switch to start a hunting movement, and means operated by current from said battery in case the switch selects said second contact in its hunting movement for stopping such hunting movement.

ll. In a telephone system, a switch, a group of lines, a special test contact for each line of said group, the special test contact of the first line in the group being permanently connected to the ungrounded pole of battery and the special testv contact of the last line in the group permanently connected to the grounded pole of battery, means for directively operating said switch to select the terminal of the first line in the group, means responsive to the battery potential on said first terminal and operative in case the first line is busy for causing said switch to automatically hunt for an idle line in said group, and means for stopping the hunting movement of the switch when the grounded last terminal is` engaged regardless of whether the last line is busy or idle.

12. In a telephone system, a group of lines, a switch having a special test wiper, a special test contact for each line of said group accessible to said wiper, thel last of said special test contacts being permanently cionnected to grounded pole of battery, means for operating said switch to hunt for an idle line in said group, and means operative responsive to the engagement of said wiper with said grounded test Contact for stopping the hunting movement.

13. In a telephone system, a rotary connecterswitch, group ot lines accessible to said switch, each line having a special test contact, and permanent connections from the first and last of said special contacts to opposite poles of the exchange battery.

14. In a telephone system, a switch having a directive movement and an automatic hunting movement, two test wipers in said switch and contacts engaged thereby responsive to the directive movement of said switch, a test relay in said switch energized over a circuit including one wiper, another relay in said switch energized over a circuit closed by said test relay through the other wiper but exeluding'the tirst wiper to start the hunting movement, and means for deenergizing said other relay over a. circuit` including said other wiper to stop the hunting movement.

15. In a telephone system, a group of lines, a'switch having two test wipers, a set ot bank contacts for each line accessiblel to said wipers, a test relay, a rotary series relay, means including the energization of said series relay for connecting said test relay to one ofthe contacts of the first set over one wiper, means responsive to said connection for energizingsaid test relay when said contact is busy, a third relay, means including the other contact of the lirst set, the other wiperand contacts on the test and series erating said switch in an automat-ic hunting movement, andmeans responsive 'to the engagement of said other wiper with one ot the contacts of the last set for deenergizing said third relay to stop the hunting movement. y

16. In a switch having an automatic hunting movement, a differential relay having two windings, means tor energizing said re lay over its first winding to canse said` switch to start its hunting movement, said relay closing a holding circuit tor itself including both windings, the iirst winding having the greatest magnetizing effect, and means for shunting the first winding and for increasing the current flow in the second winding to cause said relay to deenergize to step the hunting movement of said switch.

17. In a telephone system, a relay having two windings, means for energizing sai d rclay ovei' its first winding', contacts on said relay closed responsive to said energization for closing a locking circuit ,tor said relay, said locking circuit including both windings of said relay in series, the current tlow in said windings being in opposite direction and the second winding being less powerful than the first, and means 'for shunting the lirst winding and for increasing the current flow in the second winding to cause said relay to deenergize to open said locking cir cuit.

18. In a rotary connecter, a relay, rre-"ins including a. test wiper ot said switch 'tor energizing said relaytostart the hunting movement, and means including said test wiper for reversing the polarity of the rclay magnet, whereupon saidrelay decnergized to stop the hunting movement.V

In witness whereof, I hereunto subscribe my name this 25th day of J une, A.. D., 1925.

RUDOLPH F. STEHLIK. 

